Frequencies for first 10,000 rows of ca_gast variable in natl2014 dataset :

Gastroschis |
   is Y Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,994       99.94       99.94
          Y |          6        0.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 15 Jun 2016